There are many circumstances in which it is desirable to prevent vibrations in one structure or member from being transmitted to an adjacent structure or member. In industrial machinery, for example, vibration isolation helps to minimize noise levels in work areas, prevent damage to sensitive recording and other instrumentation, and permit proper operation of the machinery without the interference of high levels of transmitted vibration. A textile yarn processing machine is one example of an industrial machine in which there is a significant need for vibration isolation. A textile yarn processing machine typically includes at least one spindle rail that is fixed to the machine, is oriented generally horizontally, and extends along the length of the machine. The spindle rail has a number of stations, each of which is designed to support a generally vertically oriented textile spindle. Mounted on the spindle rail at each spindle station is a ring that is positioned to encircle the upper end of a textile spindle installed at the spindle station. The ring is movable vertically along the upper end of the textile spindle so as to guide yarn onto a bobbin carried by the spindle. When the ring and the spindle are properly aligned and functioning, the yarn is evenly wound on the bobbin and forms a neat package.
Because textile spindles rotate at speeds of from about six thousand (6000) to about twenty thousand (20000) revolutions per minute, a substantial amount of vibration and vibration induced noise can be generated by even a single textile spindle. In a textile plant, which may include several textile machines, each of which carries one hundred or more spindles, the noise produced can be deafening. Efforts to reduce the vibration and vibration induced noise levels in textile machinery typically involve the interposition of resilient mountings between each textile spindle and the machine rail on which the spindle is mounted. The resilience of such mountings is often provided by bodies of elastomer, as is exemplified by the textile spindle mountings described and illustrated in patents such as Olowinski et al U.S. Pat. No. 3,885,767, Olowinski U.S. Pat. No. 3,942,314, and Hannibal U.S. Pat. No. 4,045,948.
In addition to its tendency to generate vibrations and vibration induced noise when rotating, a textile spindle poses special problems as a result of the need vertically to align or plumb the spindle. If, for example, a rotating spindle is not in proper vertical alignment with the ring that moves up and down along the spindle to guide the yarn onto the bobbin carried by the spindle, the resulting yarn package will be inaccurately and unevenly wound and will tend to be unstable. The most widely used and well established method of plumbing a textile spindle is to place thin shims between a flange carried by the spindle and the machine rail on which the spindle is mounted. In such a plumbing operation, the spindle is mounted on the machine rail in a position such that the spindle is centered with reference to the ring when the ring is located closest to the machine rail. The ring is subsequently moved to its farthest position from the rail and the upper end of the spindle is centered in the ring by placing cardboard or paper shims between the machine rail and the flange carried by the spindle near its base. Although the shimming procedure is difficult, tedious, and time consuming, it is widely used and individuals who are capable of producing satisfactory results utilizing the procedure are regarded as skilled technicians in the textile industry.
An alternative to plumbing a textile spindle using paper shims is to provide a mechanical device for plumbing. An effective mechanical plumbing device should make plumbing a more routine and less time consuming procedure by eliminating the need to judge the required thicknesses and positions of shims. One type of mechanical plumbing device that has been proposed includes an annular flange or collar that is attached to or supports the base of a textile spindle. The collar is secured to the machine rail using three threaded members, such as bolts or screws, which are circumferentially and equally spaced about the collar and which extend between the collar and the machine rail. By rotating each screw or bolt in an appropriate direction, the distances between the machine rail and various portions of the collar can be adjusted. Thus, the orientation of the collar and the textile spindle relative to the machine rail is adjusted. Examples of so-called "three-point" plumbing mechanisms are described and illustrated in Scheid U.S. Pat. No. 590,378, Scheid U.S. Pat. No. 580,718, and McCombs U.S. Pat. No. 3,672,023. A somewhat similar mechanism, in which the three screws are not equally spaced about the collar, is described and illustrated in Knight et al U.S. Pat. No. 1,213,657. Other mechanical plumbing devices utilize components with mating spherical, conical, or otherwise sloped surfaces. By sliding the juxtaposed components relative to each other on their mating surfaces, the vertical alignment of a textile spindle supported by the plumbing mechanism can be changed. Examples of mechanical spindle plumbing devices that incorporate mating curved or sloped surfaces on adjacent components are described and illustrated in Scheid U.S. Pat. No. 590,377, Rowe, Jr. U.S. Pat. No. 2,954,661, Stiepel et al U.S. Pat. No. 3,364,670, and Anderson et al U.S. Pat. No. 3,835,634.
In the past, some efforts have been made to provide both vibration isolation and mechanical plumbing capability in a single mounting or support system for a textile spindle. Examples of such spindle mountings or support systems are described and illustrated in the previously mentioned Rowe, Jr. U.S. Pat. No. 2,954,661 and Stiepel et al U.S. Pat. No. 3,364,670. The plumbing procedures for the Stiepel et al mounting system are more fully described at column 3, lines 27-54 of the previously mentioned Anderson et al U.S. Pat. No. 3,835,634. Both the Rowe, Jr. spindle mounting and the Stiepel et al spindle mounting system incorporate juxtaposed metal components with mating spherical or conical surfaces to provide the necessary plumbing capability. Mating surfaces are utilized for plumbing in order to minimize the conflict between the need to fasten a textile spindle securely to a machine rail and the need to plumb the spindle. The Rowe, Jr. spindle mounting, for example, can be securely fastened to a machine rail and a textile spindle inserted into the mounting, all prior to plumbing. The orientation of the textile spindle with respect to the mounting is then adjusted by sliding two curved surfaces carried by the spindle relative to two mating surfaces carried by the mounting. When the proper vertical alignment of the spindle is achieved, a retaining nut, which provides one curved surface and is carried on the end of the spindle, is tightened down against the adjacent end of the mounting, which provides a mating curved surface. Tightening the retaining nut to secure the spindle to the mounting will not change the vertical alignment of the spindle because the two sets of mating surfaces are always in close, evenly supported contact.
In comparison to the Rowe, Jr. spindle mounting, which incorporates mating spherical surfaces for plumbing, a three-point spindle plumbing mechanism such as the device shown in the previously mentioned McCombs U.S. Pat. No. 3,672,023 poses more problems in terms of plumbing a textile spindle and securing the plumbed spindle to its supporting rail. If McCombs' plumbing device is utilized to plumb a textile spindle, the spindle cannot be securely attached to its supporting rail until after the plumbing operation is complete. Thus, as McCombs' device is being adjusted to plumb the spindle, there is some looseness between the spindle, the plumbing device, and the supporting machine rail. After the mechanical plumbing adjustments appear to be complete, a retaining nut is tightened on the base of the spindle to clamp the spindle to the plumbing device and the machine rail. Because the juxtaposed surfaces of the nut and the machine rail, for example, are flat, plumbing adjustments of the spindle will tend to place the two surfaces at a slight angle to each other and thereby prevent even contact between the surfaces. As a result, it would not be at all unusual to find that after the spindle was securely clamped in place and the play or looseness eliminated from between the spindle and the plumbing device, the spindle was no longer perfectly plumb. The retaining nut would then have to be loosened and the spindle replumbed, subject to the possibility of renewed misalignment when the spindle is again tightly clamped to the machine rail.